A terminal having a data processing capability, for example, a computer, a smart phone, a palmtop computer, a tablet computer, and a smart TV, have already been widely used in work and life nowadays. Especially, a portable intelligent terminal such as a smart phone, a personal digital assistant (PDA), a pocket personal computer (Pocket PC), and a tablet computer already becomes an indispensable tool that people take with themselves.
The terminal becomes a communications terminal after being installed with a communications module. For example, a mobile phone is a common communications terminal, and is a portable communications terminal. In addition to the communications module, a subscriber identity module (SIM) for identifying a subscriber also needs to be installed in the communications terminal. For example, a SIM card is an apparatus for identifying a communications terminal in a mobile communications system, and is also referred to as a smart card, or a user identification card. A mobile phone can be used only after a SIM card is installed. The SIM card stores, on a chip, content such as information of a subscriber of a digital mobile phone, an encrypted key, and a phone book of the user, which can be used to identify the subscriber of the mobile phone and perform processing such as encryption of voice information during a call of the subscriber.
Moreover, as the amount of information stored by the communications terminal increases, a subsequent issue of privacy protection also becomes increasingly important. Especially, a mobile phone is not only a communications tool, but also stores a lot of personal information. A grave risk of leakage of privacy information exists once the mobile phone is lost.
At present, events that mobile phones are lost or stolen often happen. In such a case, if a nonowner has a mobile phone of an owner and continues to use an original SIM card of the mobile phone, the owner may track the position of the mobile phone according to information in the SIM card. Therefore, a malicious nonowner often changes a SIM card of a mobile phone immediately after finding or stealing the mobile phone, and in this way, an owner of the mobile phone can no longer track the specific position of the mobile phone and regain the mobile phone. However, the nonowner may still view most of information in the mobile phone after turning on the mobile phone, which causes leakage of privacy information of the owner.